The present invention relates generally to a CAE waveform assessor and more particularly to an apparatus for quantifying dynamic crash pulse quality.
Automotive design techniques have undergone significant change and are frequently operating under new paradox. One such region of development is popularly known as computer-aided engineering or CAE. CAE allows engineers to design and model automotive structures and perform analysis on the integrity and safety of such structures prior to the physical construction of a vehicle. These techniques have provided for significant cost savings in the automotive design process. In addition, the timeline between conception and line production has been significantly reduced. These advantages have placed CAE into a fundamental role within modern automotive design practices.
Although CAE methodologies are widely accepted as providing cost and timesavings to the automotive industry, they often provide a variety of concerns to engineering developers. One area of concern revolves around the accuracy and reliability of CAE results. Modeling techniques, restraint conditions, loading functions, and engineering assumptions can all serve to vary the results of a CAE analysis as compared to the results of physical testing. In this vein, engineering within the CAE field have spent considerable time seeking methodologies for improving the accuracy of CAE results.
One such technique has been to develop highly specific modeling and loading forms geared toward specific applications. Physical testing is then utilized to confirm the results and accuracy of the CAE analysis. When proper correlation has been achieved, future analysis can then be performed under such strict modeling guidelines. Although this technique can prove successful, it is often associated with high costs and reduced flexibility. Often such techniques are not amenable to alteration of the engineering constraints utilized in the physical verification process. When such alterations become necessary, it is often not possible to properly evaluate the output of the resulting CAE analysis.
An area particularly vulnerable to these present methodologies of CAE verification is known as dynamic crash analysis. Dynamic crash analysis is utilized to simulate large displacement impact scenarios. Vehicle impact simulations are performed for a variety of reasons, including analysis of vehicle integrity, vehicle and passenger safety, and vehicle compliance with government standards. The use of such dynamic analysis is particularly valuable when taken in light of the large costs and destructive nature of physical automotive crash testing. The nature of the simulations, however, often involve considerable and complex analysis. This can make dynamic crash CAE simulations highly acceptable to the aforementioned analysis techniques.
Additionally, the CAE analysis is used by multiple departments within a company and by suppliers, the necessity for a controlling department to analyze and evaluate the results of such multiple departments may become necessary. A quantifiable technique for evaluating such results would not only provide engineers with confidence in the CAE results but would also provide a methodology for improving CAE techniques without the need for additional physical testing. It would, therefore, be highly desirable to have a method and apparatus for analyzing and quantifying resultant CAE waveforms such as dynamic crash pulse.
It is, therefore, an object of the present invention to provide a method and apparatus for analyzing CAE waveforms. It is a further object of the present invention to provide a method and apparatus capable of quantizing the dynamic crash pulse waveform from a CAE analysis.
In accordance with the objects of the present invention, a CAE waveform assessor is provided. The CAE waveform assessor includes a CAE resultant waveform and a reference waveform. The CAE waveform assessor further includes a time domain assessor producing a time domain index by comparing the CAE resultant waveform with the reference waveform. The CAE waveform assessor also includes a frequency domain assessor producing a frequency domain index by comparing the CAE resultant waveform with the reference waveform. Finally, the CAE waveform assessor includes an overall assessor combining the time domain index and the frequency domain index to produce an overall index.
Other objects and features of the present invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and appended claims.